Evaluation of head and neck soft tissue sarcoma 8th edition pathologic staging system and proposal of a novel stage grouping system

Nicholas C J Lee; Antoine Eskander; Joseph A Miccio; Henry S Park; Chirag Shah; Michael Rutenberg; Ali Hosni; Zain A Husain

doi:10.1016/j.oraloncology.2020.105137

Evaluation of head and neck soft tissue sarcoma 8th edition pathologic staging system and proposal of a novel stage grouping system

Oral Oncol. 2021 Mar:114:105137. doi: 10.1016/j.oraloncology.2020.105137. Epub 2021 Jan 8.

Authors

Nicholas C J Lee¹, Antoine Eskander², Joseph A Miccio³, Henry S Park³, Chirag Shah⁴, Michael Rutenberg⁵, Ali Hosni⁶, Zain A Husain⁷

Affiliations

¹ Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA; Department of Internal Medicine, University of Texas Southwestern, Dallas, TX, USA; Department of Pediatrics, University of Texas Southwestern, Dallas, TX, USA.
² Sunnybrook Health Sciences Centre, Odette Cancer Centre, Toronto, ON, Canada; Department of Otolaryngology-Head and Neck Surgery, University of Toronto, Toronto, ON, Canada.
³ Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA.
⁴ Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
⁵ Department of Radiation Oncology, University of Florida, Jacksonville, FL, USA.
⁶ Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada; Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, ON, Canada.
⁷ Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA; Sunnybrook Health Sciences Centre, Odette Cancer Centre, Toronto, ON, Canada; Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada. Electronic address: zain.husain@sunnybrook.ca.

PMID: 33422859
DOI: 10.1016/j.oraloncology.2020.105137

Abstract

Background: The AJCC 8th edition issued a dedicated staging system for head and neck soft tissue sarcomas (HN-STS) with 2 and 4 cm tumor cut-off points, as well as a T4 classification based on invasion of adjacent structures. Stage groupings were not provided due to a paucity of data.

Methods: We identified HN-STS patients undergoing primary surgery without neoadjuvant therapy patients in the Surveillance, Epidemiology, and End Results (SEER) database. We used multivariable analysis to examine adverse prognosticators. Then, using, recursive partitioning analysis (RPA), we established a stage grouping system that was externally validated in the National Cancer Database (NCDB).

Results: Multivariable analysis in the SEER cohort (N = 546) demonstrated worsened survival with tumors invading adjacent structures (P < 0.001) and increasing de-differentiation (P < 0.001). There was no prognostic difference based on size for T1-3 tumors; however, when assessed as a continuous variable, a 5 cm tumor size cut-off point was predictive of outcome. RPA generated a stage grouping system with the following five-year overall survival: RPA Stage I (pT1-3N0-1G1-2M0) 71.2%, RPA Stage II (pT4abN0-1G1-2M0/pT1-3N0-1G3-4M0) 53.4%, and RPA Stage III (pT4abN0-1G3-4M0) 17.5%. This was successfully externally validated in the NCDB cohort (P < 0.001).

Conclusions: We confirm the importance of structural invasion and grade and demonstrate that the currently used size cut-off points are not prognostic. We propose a novel stage grouping system. A 5 cm tumor size cut-off point for tumor stage should be further evaluated.

Keywords: AJCC; Head and neck cancer; Larynx; Nasopharynx; Oral cavity; Oropharynx; Sarcoma; Soft tissue sarcoma; TNM staging.

MeSH terms

Adult
Aged
Female
Head and Neck Neoplasms / diagnosis*
Head and Neck Neoplasms / pathology
Humans
Male
Middle Aged
Neoplasm Staging
Prognosis
Sarcoma / diagnosis*
Sarcoma / pathology